Podcasting as a medium was first associated with, but never limited to, audio data. As use of RSS enclosures for video spread in 2005, podcasting of video data was called, among other things, "video blogging", "video podcasting", "vlogging", "vodcasting", or "vidcasting".
For iPod compatibility, these files should be M P4s? with H.264 as the codec: http://playlistmag.com/features/2005/07/howtovodcast/index.php
Once (if) the Walker can find a way to automate the conversion of existing files, we're going to try to re-launch the Channel as a iPod-ready vodcast.